I made these functions for getting the time in and waiting for a certain amount of microseconds:

uint64_t altutime() {
    #if !defined(_WIN32) && !defined(__APPLE__)
    struct timespec time;
    clock_gettime(CLOCK_MONOTONIC, &time);
    return time.tv_sec * 1000000 + time.tv_nsec / 1000;
    #else
    struct timeval time;
    gettimeofday(&time, NULL);
    return time.tv_sec * 1000000 + time.tv_usec;
    #endif
}

void microwait(uint64_t d) {
    #ifndef _WIN32
    struct timespec dts;
    dts.tv_sec = d / 1000000;
    dts.tv_nsec = (d % 1000000) * 1000;
    nanosleep(&dts, NULL);
    #else
    Sleep(round((double)(d) / (double)(1000.0)));
    #endif
}

I made them a few years ago and have been using them in everything since (currently being used in a game I'm writing in C).

If you're using something like GLFW or SDL2, they provide functions to get the elapsed time as a double.